Method of preventing explosions



V V, V. R F., 00008.

x MEIHOD'OF PREVENTING E'XPLOSIONS,

APPLICATION 'FILED um 10. 1920.

1,376,082. Patented A i; 26. 1921.

PATENT OFFICE.

ROWAN T. F. DODDS, OF STRATFORI), ONTARIO, CANADA.

Specification of Letters Patent.

METHOD OF PREVENTING EXPLOSIONS.

Patented Apr. 26, 1921.

Application filed May 10, 1920. Serial No. 380,203.

To all whom it may concern.

Be it known that I, ROWAN T. F. Donns, a citizen of the United States, residing at Stratford, in the Province of Ontario, Do-

5 minion of Canada, have invented a new and useful Improvement in Methods of Preventing Explosions, of which the following is a full, clear, and exact description.

The present invention relates broadly to humidifiers, but more particularly to a method of preventing the creation or existence of conditions conducive to explosions, by supplying water vapor to dust laden working areas as the dust therein absorbs 5 the available moisture from the atmosphere.

The principal object of the present invention is to maintain at all times in dust laden working areas a stable atmospheric condition tending to prevent explosions.

0 A further object of the present invention is to provide a method of maintaining predetermined minimum amounts of free water vapor in dangerous working areas.

Still a further object of the invention is to localize in special instances the application of the additional water vapor whereby the desired conditions are maintained at the points of greatest danger.

The foregoing and other objects, together with their attendant advantages, will be apparent as the invention becomes better understood by reference to the accompanying specification and drawing forming a part thereof, it being premised that changes may be made in the various details and the manner of operation within the scope of the appended claims without departing from the spirit of the invention. In the drawings the figure is a diagrammatic illustration of one form of apparatus suitable for carrying out my invention.

At the present time there is annually a great loss of life and property due to explosions occurring in coal mines, flour and feed mills, grain elevators, threshing machines, separators and the like. These explosions are universally attributed to the existence in the atmosphere of amounts of dust or powder in such proportions that an explosive mixture is produced. The actual explosion of such mixtures has been brought about in various ways as by the production of sparks heat, flames or concussions. Heretofore efforts to revent such explosions have been directed toward the elimination either of the dust or powder from the atmosphere, or of the means responsible for the production of the explosion. These efforts have not overcome the danger inherent in industries in which these conditions ex- 1st and the present invention is directed, not toward the elimination either of the explosive material in the atmosphere, or of the means which bring about the explosion, but toward the prevention of an atmospheric condition capable of supporting combustion or of permitting explosions.

By a series of experiments and investigations extending over a number of years, I have found that the dust or powder present in the atmosphere possesses deliquesccnt properties and that therefore where they are present in sufficient quantities, and where the supply of fresh air is limited, they absorb all of the available moisture in the air within a predetermined working area and thereby produce an unstable atmospheric condition. As air under the common designation is composed of a large number of different independent elements combined in mechanical relationship, the elimination of the water vapor produces an unstable relation between the remaining constituents and explosions may be produced by any one of a large number of independent disturbances. The present invention aims to prevent the creation or existence of such unstable relationship by maintaining at all times a predetermined minimum of water vapor in the atmosphere by supplying additional water vapor as the free vapor is absorbed by the dust.

In the figure of the drawings there is illustrated a form of apparatus capable of preventing explosions in grain elevators or bins. As illustrated, this apparatus comprises a tank 1 of any desired construction, having a water inlet 2 controlled by a float 3 or similar device for maintaining a predetermined water level within the tank. Extending below the water level therein is a perforated pipe 4 whichis connected to a fan or other blower 5 for forcing air therethrough. This air escaping through the perforations in the pipe 4; will pick up a large amount of mois- "ture and this moisture laden air may be conducted through a suitable pipe 6 to a moisture conductor 7 extending within the elevator or bin 8, to a point adjacent the bottom thereof. This conductor may be provided with a series of openings 9 gradually increasing in size toward the bottom of the elevator or bin. By reason of this construction it will be apparent that if the bin is empty and grain is fed thereinto with the blower 5 in operation, moist air will be directed into the interior of the bin. The major portion of this air will be directed inwardly into that portion of the working area which is receiving the grain due to the provision of the largest escape openings at such point. As the grain gradually fills the bin these openings will be gradually covered and the point of application of the moist air will be gradually raised. During the entire filling operation, however, moist air will be supplied directly into that working area in which an explosion is most apt to occur. This will result in preventing the creation of an atmospheric condition rendered unstable by the elimination of water vapor, thereby negativing the possibility of an explosion.

It will be apparent that this inventlon may be applied in any desired manner 1n connection With any of the dangerous industries of the character specified herein. By the term dust or powder, as employed throughout this specification and claims, there is meant any material which combined in proper quantities with the air will produce an explosive mixture.

It has been observed that the possibility of explosions is increased in dealing with grains as these substances contain large amounts of mineral matters. My invention, therefore, as described in connection with grain bins and elevators, is particularly valuable although this application is not limited in this respect.

The advantages of the present invention arise from the method for preventing the creation or existence of an atmospheric condition conducive to explosions.

Further advantages of the invention arise from the method of directing the moist air directly into the working area possessing the most dangerous characteristics.

I claim:

1. The method of preventing explosions in dust laden Working areas, comprising supplying additional water vapor to the area as the free vapor therein is absorbed by the dust, to maintain an effective stabilizing minimum of moisture at all times, substantially as described.

2. The method of preventing explosions in dust laden working areas, comprising supplying additional water vapors locally into the most dangerous portions of said areas as the free vapor therein is absorbed by the dust, to maintain an effective stabilizing minimum moisture at all times, substantially as described.

3. The method of preventing explosions in handling material, comprising supplying water vapor to said material during the handling thereof, to prevent the creation of an unstable atmospheric condition by maintaining an elfective stabilizing minimum of moisture at all times, substantially as described.

4. The method of preventing explosions in grain elevators, comprising supplying water vapor to the interior of said elevators during the handling of the material therein as the material absorbs the available moisture, to maintain an effective stabilizing minimum or" moisture at all times, substantially as described.

5. The method of preventing explosions in grain elevators, comprising supplying additional water vapor to the interior of said elevators during the filling thereof, said water vapor being supplied at progressively higher levels as the bins become filled, to maintain an effective stabilizing minimum of moisture therein at all times, substantially as described.

6. The method of preventing explosions in grain elevators, comprising supplying additional water vapor to the interior of said elevators during the filling thereof, said water vapor being automatically supplied at progressively higher levels as the bins become filled, to maintain an effective stabilizing minimum of moisture therein at all times, substantially as described.

7. The method of preventing explosions in working areas laden with deliquescent dust, comprising the maintenance of a stabilized atmospheric condition by the addition of water vapor to the area as the free vapor therein is absorbed by the dust, substantially as described.

8. The method of preventing explosions in dust laden working areas, comprising the production of moist air, and then supplying said air to the area as the free vapor therein is absorbed by the dust, substantially as described.

In testimony whereof, I have hereunto set In hand. a

y ROWAN T. F. nonns. 

